Anchoring device with extended tabs

ABSTRACT

An anchor can be coupleable to a bone, where the anchor includes a head, a shank, a first extension, and a second extension. The head can include a distal head portion and a proximal head portion, where the proximal head portion can be open at a proximal end of the head. The shank can extend distally from the distal head portion, where the shank including a threaded portion configured to engage the bone. The second extension can be opposing the first extension, and the second extension can include a second proximal support coupled to a second end of a first elongate portion, where a first proximal support can extend transverse to the longitudinal axis, and the first proximal support portion and the second proximal support portion can be separated in a first condition and can be engaged to transfer forces there between in a second.

CLAIM OF PRIORITY

This application is a continuation of U.S. patent application Ser. No.16/387,222, filed on Apr. 17, 2019, which claims the benefit of U.S.Provisional Patent Application Ser. No. 62/669,192, filed on May 9,2018, the benefit of priority of each of which is claimed hereby, andeach of which is incorporated by reference herein in its entirety.

BACKGROUND

Orthopedic devices such as rods, plates, tethers, staples, and otherdevices can be used in various spinal procedures to correctabnormalities (e.g., scoliosis) or to address injuries (e.g., vertebralfracture). In some spinal procedures, anchors and rods can be securedalong a spinal column between one or more vertebrae to stabilize aregion of the spine. Some surgical procedures performed on the spinalcolumn using such devices have become less invasive. However, somespecial parts used in minimally-invasive spinal procedures can increasethe difficulty of the installation procedure.

OVERVIEW

In certain procedures the inventors have found extended tab pediclescrews to be beneficial and improve the speed at which a surgeon canperform the procedure. However, traditional extended tab pedicle screwssuffer from instability at the proximal end of the tabs, which cannegatively impact the surgeon's ability to take advantage of thebenefits provided by the extensions. Accordingly, a solution has beendeveloped where the proximal end of the extensions each include matingfeatures that engage the opposing extension to form a semi-rigid, butseparable, structure on the proximal end of the extended tab pediclescrew construct. The mating feature can take on different shapes, buteach mating structure can be intended to stabilize the proximal end ofthe extended tab pedicle screw construct. This stabilization can helpprevent pinching inward of the extended tabs, which can hinder toolinsertion and visibility, while still allowing for the tabs to be split,which allows for a rod to be easily passed down between the extensions.

In one example, an anchor can be coupleable to a bone, where the anchorcan include a head, a shank, a first extension, and a second extension.The head can include a distal head portion and a proximal head portion,where the proximal head portion can be open at a proximal end of thehead. The shank can extend distally from the distal head portion, andthe shank can include a threaded portion configured to engage the bone.The first extension can include a first breakaway portion coupling thefirst extension to the proximal head portion, where the first extensioncan be separable from the head at the first breakaway portion. The firstextension can include a first elongate portion extending from a firstend proximate the first breakaway portion to a second end along alongitudinal axis of the anchor, where the first elongate portion caninclude a length sufficient to extend the second end outside an incisionwhen the shank is engaged in the bone. The first extension can include afirst proximal support that can be coupled to the second end of thefirst elongate portion, where the proximal support can extend transverseto the longitudinal axis. The second extension can oppose the firstextension, and the second extension can include a second breakawayportion that can couple the second extension to the proximal headportion, where the second extension can be separable from the head atthe second breakaway portion. The second elongate portion can extendfrom a first end proximate the first breakaway portion to a second endalong a longitudinal axis of the anchor. The first elongate portion caninclude a length sufficient to extend the second end outside an incisionwhen the shank is engaged in the bone. The second extension can includea second proximal support coupled to the second end of the firstelongate portion, where the proximal support can extend transverse tothe longitudinal axis, and where the first proximal support portion andthe second proximal support portion can be separated in a firstcondition and engaged to transfer forces there between in a secondcondition. The first and second extensions can include a threadedportion on internal faces of the first and second extensions, where thethreaded portion can extend distally from the first and secondextensions into the head portion.

This overview is intended to provide an overview of subject matter ofthe present patent application. It is not intended to provide anexclusive or exhaustive explanation of the invention. The detaileddescription is included to provide further information about the presentpatent application.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numeralsmay describe similar components in different views. Like numerals havingdifferent letter suffixes may represent different instances of similarcomponents. The drawings illustrate generally, by way of example, butnot by way of limitation, various embodiments discussed in the presentdocument.

FIG. 1 illustrates an isometric view of an anchor with extended tabs, inaccordance with at least one example of this disclosure.

FIG. 2A illustrates cross-sectional view of an anchor with extended tabsacross section 2-2 of FIG. 1, in accordance with at least one example ofthis disclosure.

FIG. 2B illustrates cross-sectional view of a portion of an anchor withextended tabs across section 2-2 of FIG. 1, in accordance with at leastone example of this disclosure.

FIG. 3 illustrates an isometric view of an anchor with extended tabsfrom a top perspective, in accordance with at least one example of thisdisclosure.

FIG. 4A illustrates an isometric front view of an anchor and sleeveassembly, in accordance with at least one example of this disclosure.

FIG. 4B illustrates an isometric side view of an anchor and sleeveassembly, in accordance with at least one example of this disclosure.

FIG. 5A illustrates an isometric top view of an anchor and sleeveassembly, in accordance with at least one example of this disclosure.

FIG. 5B illustrates an isometric side view of a portion of an anchor andsleeve assembly, in accordance with at least one example of thisdisclosure.

FIG. 5C illustrates an isometric bottom view of a button of an anchorand sleeve assembly, in accordance with at least one example of thisdisclosure.

FIG. 6 illustrates an isometric view of an anchor with extended tabs, inaccordance with at least one example of this disclosure.

FIG. 7 illustrates an isometric top view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 8 illustrates an isometric front view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 9 illustrates an isometric top view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 10 illustrates an isometric front view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 11 illustrates an isometric top view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 12A illustrates an isometric top view of an anchor with extendedtabs in a first condition, in accordance with at least one example ofthis disclosure.

FIG. 12B illustrates an isometric top view of an anchor with extendedtabs in a second condition, in accordance with at least one example ofthis disclosure.

FIG. 13A illustrates an isometric front view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 13B illustrates an isometric back view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 14A illustrates a front view of an anchor with extended tabs, inaccordance with at least one example of this disclosure.

FIG. 14B illustrates an isometric front view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 15A illustrates a front view of an anchor with extended tabs, inaccordance with at least one example of this disclosure.

FIG. 15B illustrates an isometric front view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 16 illustrates an isometric front view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 17 illustrates an isometric front view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 18 illustrates a front view of an anchor with extended tabs, inaccordance with at least one example of this disclosure.

FIG. 19 illustrates a front view of an anchor with extended tabs, inaccordance with at least one example of this disclosure.

FIG. 20A illustrates a front view of an anchor with extended tabs, inaccordance with at least one example of this disclosure.

FIG. 20B illustrates an isometric view of an anchor with extended tabs,in accordance with at least one example of this disclosure.

FIG. 20C illustrates an isometric top view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 20D illustrates an isometric side view of an anchor with extendedtabs, in accordance with at least one example of this disclosure.

FIG. 21 illustrates a front view of an anchor with extended tabs, inaccordance with at least one example of this disclosure.

DETAILED DESCRIPTION

Bone anchors can be used together with connecting members (such as rigidand semi-rigid rods) to straighten a region of a human spine to addressan abnormality (e.g., scoliosis), to stabilize a spine following aninjury (e.g., fractured vertebrae), or to address degeneration of thespine caused by disease. In minimally invasive spinal procedures toaddress these issues, multiple small incisions can be made to formmultiple small cavities near individual vertebrae. A large amount of theprocedure is performed through manipulation of instruments andcomponents extending through the small surgical cavities using specialinstruments that are able to be manipulated from outside of thecavities. For example, anchors are commonly driven into vertebrae, wherethe anchors include extended tabs rigidly coupled to the anchors andhaving a length sufficient to extend outside of the cavity so that theanchors (and components engaging the anchors) can be manipulated fromoutside of the cavities. Because the extended tabs comprise a lengthsufficient to extend through the cavities, they often must be separablefrom the heads of the anchors (which remain secured to vertebrae).Further, because the extensions often need to receive a connectingmember and a closure top, the extensions must often be of a quantity ofat least two to allow threading of the closure top into the head of theanchor and to provide a slot to reduce and retain the connecting member.

Some designs include two extensions each coupled to the head of theanchor at a breakaway portion, where each extended tab can beindividually bent to allow separation of the extension from the head atthe breakaway portions. This design requires relative movement of theextended tabs for separation. However, the extended tabs must also berigid enough to transfer forces between the tabs. Sometimes the forcesmust be transferred from a portion of the extended tabs external to thecavity to a portion of the extended tabs into the cavity and ultimatelyto the head and/or shank of the anchor. To allow individual separationof the extended tab while also allowing transfer of forces and torquesof the tabs without unintended separation of the extension from thehead, extensions are often formed together at a proximal end of theextensions. In these cases, the extensions must be separated or brokenaway from each other in order to facilitate breaking off each extensionfrom the pedicle screw. Separation can increase a risk of material beinglost into a cavity and adds another step to the procedure.

This disclosure addresses these problems with extended tabs by includingsupport pieces that do not require separation. More specifically, tosolve the problem of allowing transfer of torque and forces between theextensions without requiting separation of the extended tabs, whilehelping to avoid unwanted pinching in of the extended tabs during theprocedure, this disclosure proposes proximal supports extending from aproximal end of each extended tab that are not formed together (or areseparate). The proximal supports can be engaged with each other to allowtransfer of torque and/or forces between the supports (and thereforebetween the extended tabs); however, the supports do not requireseparation, which can help reduce debris produced during a procedure andcan save the step of separation of the extended tabs, which can savetime during the procedure. This disclosure also addresses the problem ofallowing individual separation of the extended tab while allowingtransfer of forces and torques of the tabs without unintended separationof the extension from the head by providing a sleeve couplable to theanchor where the sleeve can transfer forces directly to and from thehead of the anchor instead of to and from the extended tabs.

FIG. 1 illustrates an isometric view of anchor 100 with extended tabs,in accordance with at least one example of this disclosure. Anchor 100can include head 102, shank 104, and extensions 106 and 108. Head 102can include channel 110, head threading 112, and breakaway portions 114and 116. Extensions 106 and 108 can include extension threading 118,channels 120 (only 1 visible in FIG. 1), and proximal opening 122.Extension 106 can include elongate portion 124 and proximal supports 128a and 128 b. Extension 108 can include elongate portion 126 and proximalsupports 130 a and 130 b. Also shown in FIG. 1 are axis A, length L,torque T1, and orientation indicators Proximal and Distal.

The components of anchor 100 can be comprised of rigid and semi-rigidmaterials such as metals, plastics, composites, and the like. In someexamples, anchor 100 can be comprised of bio-compatible materials, suchas stainless steel, titanium, and the like. In some examples, anchor 100can be comprised of only one material and can be comprised of multiplematerials in other examples.

Head 102 can be a head of anchor 100 where head 102 can be coupled toshank 104 at a distal portion of head 102 with shank 104 extendingdistally therefrom and where axis A can be a central axis for head 102and shank 104. In other examples, shank 104 can deviate from axis A atvarious angles. Shank 104 can be a threaded shank or screw includingmale threads configured to engage bone, such as a relatively coarsethread pattern. In some examples, shank 104 can be configured tothreadably secure to a vertebra of a spine of a human. Shank 104 can bean integral component to head 102 in some examples, coupled to a distalportion of head 102. In other examples, shank 104 can be a portion of afastener that is a separate component from head 102 and can be disposedwithin a bore of head 102 and configured to be retained therein.

Channel 110 of head 102 can be generally U-shaped in some examples, andcan be configured to receive a connecting member (such as a connectingrod or wire) therethrough. In some examples, head 102 can have flatsides and one or more tool interfaces, as discussed further below.Breakaway portions 114 and 116 can be a portion of anchor 100 couplinghead 102 to extensions 106 and 108, where breakaway portions 114 and 116can have a thickness that is smaller than a thickness of head 102 orextensions 106 and 108 that surrounds breakaway portions 114 and 116.The reduced thickness of breakaway portions 114 and 116 can facilitateseparation and removal of extensions 106 and 108 from head 102, asdiscussed further below.

Head threading 112 can be a female threaded portion within channel 110of head 102. Head threading 112 can be aligned with extension threading116 and can be of the same thread type (spacing, pitch, etc.) asextension threading 112. In some examples, head threading 112 can berelative fine threading (such as machine-type threading) configured toreceive a component having male threading, such as a closure top or setscrew configured to retain a connecting member or rod.

Extensions 106 and 108 can include elongate portion 124 and elongateportion 126, respectively, which can be substantially longitudinalbodies extending substantially proximally from head 102 andsubstantially parallel to axis A. In some examples, elongate portions124 and 126 can have a length L sufficient to extend a proximal end ofextensions 106 and 108 outside an incision when shank 104 is engaged ina bone. Together, elongate portions 124 and 126 can form an incompletehollow cylinder separated by channels 120. Channels 120 can be slotsbetween elongate portions 124 and 126 that substantially align withchannels 110 of head 102. Extensions 106 and 108 can be coupled to head102 by break off portions 114 and 116, as noted above. In some examples,extension threading 118 can be relative fine threading (such asmachine-type threading) configured to receive a component having malethreading, such as a closure top.

Proximal supports 128 a and 128 b can extend substantially orthogonally(or transversely) from a proximal portion of elongate portion 124 andproximal supports 130 a and 130 b can extend substantially orthogonally(or transversely) from a proximal portion of elongate portion 126.Proximal supports 128 a and 128 b and proximal supports 130 a and 130 bcan extend toward each other in some examples, such that terminations ofproximal support 128 a and proximal support 130 a can be adjacent andseparated in a first condition and can engage to transfer forces and/ortorques there between in a second condition.

Extensions 106 and 108 can also include proximal opening 122 formed byelongate portion 124, elongate portion 126, proximal support portions128 a and 128 b, and proximal support portions 130 a and 130 b. In someexamples, proximal opening 122 can be sized to receive a fastenertherethrough, where the fastener can be passed distally betweenextension 106 and 108 to extension threading 118.

In operation of some examples, once a patient's spinal region (andspecifically a vertebra) is prepared (as discussed below), anchor 100can be extended into an incision and aligned with a portion of thevertebra (for example a guide bore) configured to receive shank 104. Inthis condition, proximal support portions 128 a and 128 b can beadjacent to proximal support portions 130 a and 130 b but may not be incontact in some examples. In other examples, proximal support portions128 a and 128 b and proximal support portions 130 a and 130 b can be incontact, but can be entirely separate components.

Once shank 104 is engaged with the bore of the vertebra, torque T1 canbe applied to head 102 about axis A using a tool. When torque T1 isapplied to head 102, Torque T1 can be transferred proximally upextensions 106 and 108 and can then be transferred between extensions106 and 108 through proximal support portions 128 a and 128 b andproximal support portions 130 a and 130 b. For example, torque T1 can betransferred between support portions 128 a and 130 a and can betransferred between support portions 128 b and 130 b, helping to preventpinching in of extensions 106 and 108 during driving of shank 104 intobone.

Once shank 104 is secured into the vertebra, a connecting member can bepassed through slots 120 between extensions 106 and 108 and can bereduced down through channels 120 and into channel 110 of head 102. At alater time, or during reduction, a closure top (or other fastener) canbe pass through proximal opening 122 and can be threaded into extensionthreading 118 and down to head threading 112 and into channel 110 ofhead 102 to retain the connecting member.

During reduction, especially when using a set screw to reduce a rodthrough extensions 106 and 108, forces and torques can be applied toextensions 106 and 108 when torque T1 is applied to the set screw. Thistorque (or the resulting forces) can be transferred between supportportions 128 a and 130 a and can be transferred between support portions128 b and 130 b to reduce flexing of tabs 106 and 108 at breakawayportions 114 and 116. Breakaway portions 114 and 116 can be of asufficient thickness to transfer forces and torques between extensions106 and 108 and head 102 during reduction without causing separation ofextensions 106 and 108 from head 102. Also, because proximal supportportions 128 a and 130 a engage each other and 128 b and 130 b engageeach other during transfer of these forces, movement of elongateportions 124 and 126 relative to head 102 is reduced, helping to preventunwanted breakaway of extensions 106 and 108 during the process ofdriving shank 104 into bone.

Because proximal support portions 128 a and 128 b and proximal supportportions 130 a and 130 b are configured to be separate but engageable,proximal support portions 128 a and 128 b and proximal support portions130 a and 130 b allow for the transfer of torque and forces therebetween without requiring proximal support portions 128 a and 128 b tobe formed together. Because proximal support portions 128 a and 128 b donot have to be separated from 130 a and 130 b, less debris may beproduced and a step of separation of extended tabs 106 and 108 can beeliminated, which can save time during the procedure.

FIG. 2A illustrates cross-sectional view of anchor 100 across section2-2 of FIG. 1, in accordance with at least one example of thisdisclosure. FIG. 2B illustrates cross-sectional view of a portion ofanchor 100 across section 2-2 of FIG. 1, in accordance with at least oneexample of this disclosure. FIGS. 2A and 2B are discussed belowconcurrently.

Anchor 100 can include head 102 and extensions 106 and 108. Head 102 caninclude channel 110, head threading 112, breakaway portions 114 and 116,proximal head portion 132, distal head portion 134, shank bore 136, andtool interface 138. Extensions 106 and 108 can include extensionthreading 118, channels 120 (only 1 visible in FIGS. 2A and 2B), andproximal opening 122. Extension 106 can include elongate portion 124 andextension 108 can include elongate portion 126. Extension 106 caninclude proximal supports 128 a and 128 b (only proximal support 128 bis visible in FIG. 2A) and extension 108 can include proximal supports130 a and 130 b (only proximal support 130 b is visible in FIG. 2A).Extensions 106 and 108 can terminate at proximal extension portion 140.Also shown in FIGS. 2A and 2B are thickness t1, thickness t2, axis A,and orientation indicators Proximal and Distal.

Anchor 100 of FIGS. 2A and 2B can be consistent with anchor 100 of FIG.1; however, FIGS. 2A and 2B show additional details of anchor 100. Forexample, FIG. 2 shows a position of proximal head portion 132 near wherehead portion couples to extensions 106 and 108 via breakaway portions114 and 116. Distal head portion 134 can be located near a distaltermination of head 102.

Shank bore 136 can be an internal central bore of head 102 open to aproximal end of proximal portion 134 of head 102. Shank bore 136 can beconfigured and sized to receive and retain an anchor or shank (such asshank 102 of FIG. 1) therein. In some examples, shank bore 136 can besized to prevent rotation of the shank relative to head 102.

FIGS. 2A and 2B also show rim interface 137 of head 102. Rim interface137 can be a notch, slot, recess, and the like in opposing sides of head102. Rim interface 137 can be sized to receive a tab or projection at adistal portion of a sleeve to retain the sleeve on anchor 100.

FIGS. 2A and 2B also show tool interface 138 of head 102. Tool interface138 can be a notch, slot, recess, and the like in opposing sides of head102. Tool interface 138 can be sized to receive a tool or portion of atool therein. FIGS. 2A and 2B also show how breakaway portions 114 and116 can have a reduced thickness. For example, breakaway portion 114 canhave thickness t1, as shown in FIG. 2B and adjacent portions of head 102and extension 106 can have thickness t2, which can be larger thanthickness t1. This can allow for extension 106 to be bent at breakawayportion 114, allowing for separation of extension 106 from head 102 atbreakaway portion 114. In other examples, thickness t1 can be the samethickness as thickness t2. In some other example, thickness t1 can besmaller than thickness t2, but can have a radially inner diameter thatis the same as that of threading 118, noted at thickness t2.

FIG. 3 illustrates an isometric view of anchor 100 from a topperspective, in accordance with at least one example of this disclosure.Anchor 100 can include head 102 and extensions 106 and 108. Extensions106 and 108 can include slots 120 a and 120 b, proximal opening 122, andproximal extension portion 140. Extension 106 can include elongateportion 124, and proximal supports 128 a and 128 b. Extension 108 caninclude elongate portion 126, and proximal supports 130 a and 130 b.Proximal support 128 a can include support end 142 which can includeface 144. Proximal support 128 b can include support end 146 which caninclude face 148. Proximal support 130 a can include support end 150which can include face 152. Proximal support 130 b can include supportend 154 which can include face 156. Also shown in FIG. 3 are axis A,chords C1 and C2, radial thicknesses R1, R2, and R3, and forces Fx andFy.

Anchor 100 of FIG. 3 can be consistent with FIGS. 1-2B; however, FIG. 3shows further details of anchor 100, especially proximal supports 128 aand 128 b and 130 a and 130 b. For example, FIG. 3 shows how eachproximal support includes an end having a face. Support end 142 canterminate at face 144 and support end 150 can terminate at face 152where faces 144 and 152 can be parallel in a first condition (shown inFIG. 3) and separated by gap 160 having a distance G. Similarly, supportend 146 can terminate at face 148 and support end 154 can terminate atface 156 where faces 148 and 156 can be parallel in a first condition(shown in FIG. 3) and separated by gap 158 having a distance G. In theexample shown in FIG. 3, faces 144 and 152 can be substantially parallelto a first plane that is substantially parallel with chord C1 that istransverse to axis A. Faces 148 and 156 can be substantially parallel toa second plane that is substantially parallel with chord C2 that istransverse to axis A. In the example of FIG. 3, the chords C1 and C2 arenot the same chord and are not parallel chords. In some examples, chordsC1 and C2 can have the same angle θ relative to a diameter of axis A.

Also shown in FIG. 3 are radial thicknesses R1, R2, and R3. Radialthickness R1 can be a thickness of extension 106 proximate proximal end140 and thickness R3 can be a thickness of proximal support 128 bproximate proximal end 146 and thickness R2 can be a reduced thicknessat notches 131 where each proximal support connects to each longitudinalportion (e.g., where proximal support 128 b connects to longitudinalportion 124). In operation of some examples, radial thickness R2 canallow for a sleeve to slide over extended tabs 106 and 108. In someexamples, radial thickness R2 can ensure that the sleeve is correctlyoriented (or clocked) with respect to tabs 106 and 108, as discussedfurther below.

In operation of some examples, faces 144 and 152 can be separated by gap160 and faces 148 and 156 can be separated by gap 158 in a firstcondition. Because extensions 106 and 108 can flex toward each other andbecause the proximal extensions of each extension can deflect towardseach other, when forces and/or torques are applied to extensions 106 and108, faces 144 and 152 can contact each other and/or faces 148 and 156can contact each other to transfer forces there between. Because faces144 and 152 are not parallel with faces 148 and 156, proximal support128 a is less likely to disengage proximal support portion 130 a andproximal supports 128 b is less likely to disengage proximal supportportion 130 b, helping to ensure forces and torques are transferrablebetween the proximal supports and helping to prevent extensions 106 and108 from separating unintentionally. For example, forces transverse toaxis A such as Fx and Fy can be transferred between faces 144 and 152 toallow transfer of forces between extensions 106 and 108 and thereforefrom head 102 to a proximal end of extensions 106 and 108. In someexamples, forces may be applied to extensions 106 and/or 108 when aconnecting rod is being reduced into position in head 102.

FIG. 4A illustrates an isometric front view of assembly 200, inaccordance with at least one example of this disclosure. FIG. 4Billustrates an isometric side view of assembly 200, in accordance withat least one example of this disclosure. FIGS. 4A and 4B are discussedconcurrently below. FIGS. 4A and 4B below discuss how sleeve 202 can beused to reinforce extended tabs 106 and 108.

Assembly 200 can include anchor 100 and sleeve 202. Anchor 100 caninclude head 102 and can be consistent with anchor 100 of FIGS. 1-3above. Sleeve 202 can include arms 204 and 206, proximal portion 208,slots 210, distal end 212, and button 214.

Sleeve 202 can be a generally hollow cylindrical member including anelongate body having a central bore 216, where central bore 216 can besized and shaped to receive anchor 100 therein. Arms 204 and 206 canextend distally from proximal portion 208 and can be separated bychannels 210, which can be sized to align with channels 110 of anchor100. Arms 204 and 206 can have a length sized to extend over extensions106 and 108 of anchor, while exposing most of head 102. In someexamples, arms 204 and 206 can have a length sized to extend over head102.

In some examples, a distal portion of arms 204 and 206 can include aninternal counterbore which can include a dovetail feature sized to allowsleeve 202 to slide over extended tabs 106 and 108 and to engage head102 to limit axial translation and rotation of anchor 100 relative tosleeve 202. Button 214 of proximal portion 208 can be operable to securesleeve 202 to, and release sleeve 202 from, anchor 100, as describedbelow in FIGS. 5A-5C.

In operation of some examples, a proximal portion of anchor 100 can beinserted into distal opening 220 of sleeve 202 and can be inserted untilradially inwardly extending projections of sleeve 202 engage riminterface 137 of head 102 of anchor 100. Anchor 100 can be inserted intosleeve 202 either before or after anchor 100 is inserted into a cavityand before or after anchor 100 is secured to a bone. Once anchor 100 issecured within sleeve 202, and after anchor is driven into bone, aconnecting member or rod can be inserted. The connecting member caneither be passed through slots 120 of anchor and passed through slots210 of sleeve at the same time, or the connecting member can be passedthrough slots 120 of anchor and the sleeve 202 can be inserted overanchor 100 where the distal openings of slots 210 can receive theconnected member into slots 210 of sleeve 202.

Once the rod or connecting member is reduced into place, a closure topor fastener (e.g., set screw) can be used to secure or reduce aconnecting member into head 102. with sleeve 202 preventing prematurebreakage at 114 and 116 during this reduction. In some examples, theclosure top or set screw can be used to reduce the rod through extendedtabs 106 and 108. In this example, sleeve 202 can reinforce tabs 106 and108 to help prevent premature breakage at 114 and 116 during reduction.Sleeve 202 can also be used to reinforce extended tabs 106 and 108 toprevented unwanted break off when other external forces and torques areapplied to extended tabs 106 and 108. In one example, sleeve 202 canreinforce tabs 106 and 108 during hand positioning or manipulation ofanchor 100, such as when rotating an anchor already secured to avertebral body. This type of hand positioning and rotation of sleeve 202and anchor 100 can be common during a spinal de-rotation procedure.

FIG. 5A illustrates an isometric top view of assembly 200, in accordancewith at least one example of this disclosure. FIG. 5B illustrates anisometric side view of a portion of assembly 200, in accordance with atleast one example of this disclosure. FIG. 5C illustrates an isometricbottom view of button 214 of assembly 200, in accordance with at leastone example of this disclosure. FIGS. 5A-5C are discussed concurrentlybelow.

Assembly 200 and anchor 100 shown in FIGS. 5A-5C can be consistent withFIGS. 1-4B discussed above; however, FIGS. 5A-5C show additional detailsof assembly 200 and especially of sleeve 202. For example, FIG. 5A showsprojections 224 a-224 d that can extend radially inward from bore 226 ofsleeve 202 and can extend from a proximal end of proximal portion 208 toor near a distal portion of sleeve 202. In operation, projections 224a-224 d can each interface with one of notches 131 (shown in FIG. 3)allowing sleeve 202 to interlock with extended tabs 106 and 108 ofanchor 100, helping to limit rotation of sleeve 202 relative to anchor100. Though four of projections 224 a-224 d are shown, more or less canbe used. For example, 1, 2, 3, 5, 6, 7, 8, and the like projections canbe used. Though projections 224 a-224 d are shown to have a generallytriangular shape, other shapes can be used.

FIG. 5A also shows how button 214 is insertable into button recess 222of sleeve 202. This can allow button 214 to engage anchor 100 (asdiscussed below) and can reduce an amount button 214 extends beyond anouter radial surface of sleeve 202. This can help to reduce button 214from catching on instruments and other objects during a procedure.

FIGS. 5B and 5C show button 214 and how button 214 interacts with anchor100. For example, FIG. 5C shows button projection 228, which can be aprotuberance extending from a bottom surface of button 214. FIG. 5C alsoshows recess 232 which can be a cavity or recess into a bottom surfaceof button 214. In some examples, recess 232 can be sized to retain aspring and can also be sized to receive boss 236 of sleeve 202, suchthat boss 236 of sleeve 202 can extend into recess 232 when force F isapplied to button 214. Recess 232 can limit movement of a springrelative to boss 236 and therefore sleeve 202. FIG. 5C also shows buttonbore 230, which can be sized to receive pin 234 therethrough.

FIG. 5B shows how button 214 interacts with sleeve 202. For example,button 214 is disposable within button recess 222 such that button bore230 aligns with pin bore 238 of sleeve 202 allowing pin 234 to extendthrough button bore 230 and pin bore 238 so that button 214 can pivotwithin recess 222 about pin 234. In some examples, button projection 228can extend into one of projection bores 170 and 172 in a first position,as shown in FIG. 5B.

Button 214 can be biased to pivot to the first position by one or morebiasing elements, such as a spring, so that projection 228 of button 214engages projection bore 170 to limit axial movement of anchor 100relative to sleeve 202. Then, when it is desired to remove sleeve 202from anchor 100, force F can be applied to proximal portion 240 ofbutton 214 to pivot button 214 about pin 234, removing projection 228from projection bore 170 and allowing sleeve 202 to move axially suchthat sleeve 202 can be removed from anchor 100.

FIG. 6 illustrates an isometric view of anchor 600, in accordance withat least one example of this disclosure. Anchor 600 can include head602, shank 604, first extension 606, and second extension 608. Alsoshown in FIG. 6 are cutaneous portion 50, opening 52, and vertebrae V1,V2, and V3.

Anchor 600 of FIG. 6 can be consistent with anchor 100 discussed above,apart from the differences discussed below with respect to FIG. 7. Also,FIG. 6 shows how anchor 600 can be used in an example operation. Inoperation of some examples, an incision can be made on a posteriorportion of a patient along the patient's vertebral column, for example,along the patient's thoracic spine. For example, an incision can be madeon cutaneous portion 50 where the incision extends through the dermisand subcutaneous tissue to create opening 52 and exposes or partiallyexposes vertebrae V1-V3. In some cases, multiple incisions can be madeto minimize invasion. Next, a punch may be used to break the corticalbone to create a pilot or guide hole in a vertebra for anchor 600. Oncethe vertebra (for example, vertebra V1) is prepared, anchor 600 can beextended into opening 52 such that anchor 600 can be engaged withvertebra V1, for example. Shank 604 of anchor 600 can then be driveninto, for example, a pedicle of vertebra V1 to secure anchor 600 tovertebra V1 while extensions 606 and 608 can extend beyond opening 52.

While in this position, extensions 606 and 608 can receive a supportinstrument thereon and extensions 606 and 608 and/or the instrument canbe manipulated by hand to position vertebra V1, such as during ade-rotation procedure. During this rotation, the instrument and proximalsupports can help prevent unwanted separation of extensions 606 and 608.

FIG. 7 illustrates an isometric top view of anchor 600, in accordancewith at least one example of this disclosure. Anchor 600 can includehead 602, first extension 606 and second extension 608. First extension606 can include elongate portion 624 and proximal supports 628 a and 628b. Second extension 608 can include elongate portion 626 and proximalsupports 630 a and 630 b. First extension 606 and second extension 608can include slots 620 and proximal opening 622. Proximal support 628 acan include support end 642 which can include face 644. Proximal support628 b can include support end 646 which can include face 648. Proximalsupport 630 a can include support end 650 which can include face 652.Proximal support 630 b can include support end 654 which can includeface 656. Each of first extension 606 and second extension 608 caninclude notch 662. Proximal support 628 a can also include overlappingportion 664 and inner face 668. Proximal support 630 a can also includenesting portion 666 and outer face 670. Also shown in FIG. 7 areorientation indicators Proximal and Distal.

Anchor 600 can be consistent with anchor 100 discussed above withrespect to FIGS. 1-5C, except that a proximal portion of anchor 600 canbe different. For example, notch 662 of each of first extension 606 andsecond extension 608 can be a undercut or recess in an outer surface ofeach of extension 606 and second extension 608 proximate a proximaltermination of each of extension 606 and second extension 608. In someexamples, notch 662 can be sized and configured to engage with othertools (such as a driver) in other examples.

Anchor 600 also differs from anchor 100 in that it can includeoverlapping proximal supports. That is, proximal supports 628 a and 628b can substantially form a c-shape from a top or proximal perspectiveand proximal supports 630 a and 630 b substantially form a c-shape froma top or proximal perspective, where proximal supports 630 a and 630 bcan nest within proximal supports 628 a and 628 b.

For example, proximal support 628 a can include an undercut andoverlapping portion 664, which can extend circumferentially beyond face644. The undercut or notch can be defined by face 644 (which can beradially extending) and face 668 (which can be circumferentiallyextending). Nesting portion 666 of proximal support 630 a can includeface 652 which can be a radially extending face engageable with face644. Nesting portion 666 can also include face 670 which can be acircumferentially extending and radially outer face of nesting portion666 that can interface with face 668. In operation, when nesting portion666 is nested within the undercut of proximal support 628 a, forces andtorques (such as those produced by torque T) can be transferred betweenface 644 and face 652 and between face 668 and 670. Also, the nesting ofproximal supports 630 a and 630 b can help reduce unwanted separation ofextensions 606 and 608 from head 602.

FIG. 8 illustrates an isometric front view of anchor 800, in accordancewith at least one example of this disclosure. FIG. 9 illustrates anisometric top view of anchor 800, in accordance with at least oneexample of this disclosure. FIGS. 8 and 9 are discussed belowconcurrently.

Anchor 800 can include head 802, first extension 806 and secondextension 808. First extension 806 can include elongate portion 824 andsecond extension 808 can include elongate portions 826, where elongateportions 824 and 826 can define slots 820 there between. First extension806 can also include proximal supports 828 a and 828 b and secondextension 808 can include proximal supports 830 a and 830 b, which candefine proximal opening 822. Proximal support 828 a can include face 844and proximal support 830 a can include face 852 where faces 844 and 852together form notch 860. Similarly, proximal support 828 b can includeface 848 and proximal support 830 b can include face 856 where faces 848and 856 together form notch 858.

Each of notches 858 and 860 can be located at a junction betweenproximal supports. For example, notch 858 can be formed by a meeting offaces 848 and 856 such that bridge 878 remains, connecting proximalsupports 828 a and 830 a, where bridge 878 can have a thickness t. Notch860 can similarly connect proximal supports 828 b and 830 b.

In operation of some examples, torque T can be transferrable betweenproximal supports 828 a and 830 a through bridge 878 to allow a torqueto be transferred from a proximal end of anchor 800 to a distal end(head 802) to drive a shank into a bone. Torque T can be similarlytransferred between proximal supports 828 b and 830 b. In some examples,bridge 878 can allow torque T (and forces) to be transferred betweenproximal supports while helping to prevent unwanted breakaway ofextensions 806 and 808 from head 802.

Notch 860 can have an acute angle in some examples, and an obtuse anglein other examples. The angle θ, of notch 860 can be selected based on adesired amount of force required to separate proximal supports 828 fromproximal supports 830. In some examples, proximal supports 828 fromproximal supports 830 can be formed of one piece to create notches 858and 860, such as through machining processes.

First extension 806 can also include interface portion 874 and secondextension 808 can also include interface portion 876. Each of interfaceportions 874 and 876 can be a flat portion or face in an outer surfaceof each of extension 806 and second extension 808, respectively,proximate a proximal termination of each of extension 806 and secondextension 808. In some examples, each of interface portions 874 and 876can be sized and configured to engage with a support instrument in someexamples, and can be configured to engage with other tools (such as adriver) in other examples.

FIG. 10 illustrates an isometric front view of anchor 1000, inaccordance with at least one example of this disclosure. FIG. 11illustrates an isometric top view of anchor 1000, in accordance with atleast one example of this disclosure. FIGS. 10 and 11 are discussedbelow concurrently.

Anchor 1000 can include head 1002, first extension 1006, and secondextension 1008. First extension 1006 can include elongate portion 1024,proximal supports 1028 a and 1028 b, projection bore 1070, distalprojection 1080, and proximal projection 1082. Second extension 1008 caninclude elongate portion 1026, proximal supports 1030 a and 1030 b,projection bore 1070, distal projection 1080, and proximal projection1082.

Anchor 1000 can be similar to anchor 600 in that proximal supports 1028a and 1028 b can have a geometric shape that is substantially a c-shapeand proximal supports 1030 a and 1030 b can have a geometric shape thatis substantially a c-shape that nests within proximal supports 1028 aand 1028 b. For example, nesting portion 1066 of proximal support 1030 acan nest within proximal support 1028 a such that overlapping portion1064 overlaps nesting portion 1066.

Anchor 1000 can differ from anchor 600 in that anchor 1000 includesdistal projections 1080 and proximal projections 1082. Proximalprojections 1082 can extend radially from outer surfaces of elongateportions 1024 and 1026. Each of proximal projection 1082 can have asubstantially rectangular prismatic shape that is axially extending andcan be configured to interact with a channel of a sleeve, in someexamples.

Similarly, distal projections 1080 can extend radially from outersurfaces of elongate portions 1024 and 1026. Each of distal projections1082 can substantially form an axially extending tail configured toengage a socket of a sleeve (similar to sleeve 202 of FIGS. 4A-5C)similar to a dovetail engagement, and can be configured to engage withother tools (such as a driver) in other examples.

FIG. 12A illustrates an isometric top view of anchor 1200 in a firstcondition, in accordance with at least one example of this disclosure.FIG. 12B illustrates an isometric top view of anchor 1200 in a secondcondition, in accordance with at least one example of this disclosure.FIGS. 12A and 12B are discussed below concurrently.

Anchor 1200 can include head 1202 and extensions 1206 and 1208.Extension 1206 can include elongate portion 1224, and proximal supports1228 a and 1228 b. Extension 1208 can include elongate portion 1226, andproximal supports 1230 a and 1230 b. Proximal support 1228 a can includesupport end 1242 which can include face 1244. Proximal support 1228 bcan include support end 1246 which can include face 1248. Proximalsupport 1230 a can include support end 1250 which can include face 1252.Proximal support 1230 b can include support end 1254 which can includeface 1256. Also shown in FIG. 12 are axis A and chords C1 and C2.

Anchor 1200 of FIG. 12 can be similar to anchor 300 of FIG. 3 withdiffering proximal supports. Support end 1242 can terminate at face 1244and support end 1250 can terminate at face 1252 where faces 1244 and1252 can be parallel in a first condition (shown in FIG. 12A) andseparated by gap 1260 having a distance G. Similarly, support end 1246can terminate at face 1248 and support end 1254 can terminate at face1256 where faces 1248 and 1256 can be parallel in a first condition(shown in FIG. 12A) and separated by gap 1258 having a distance G.

In the example shown in FIG. 12A, faces 1244 and 1252 can besubstantially parallel to a first plane that is substantially parallelwith chord C1 that is transverse to axis A and faces 1248 and 1256 canbe substantially parallel to a second plane that is substantiallyparallel with chord C2 that is transverse to axis A. In the example ofFIG. 12A, the chords C1 and C2 can be parallel (and can be the samechord).

In operation of some examples, faces 1244 and 1252 can be separated bygap 1260 and faces 1248 and 1256 can be separated by gap 1258 in a firstcondition (shown in FIG. 12A). Because extensions 1206 and 1208 can flextoward each other and because the proximal extensions can deflecttowards each other, when forces and/or torques are applied to extensions1206 and 1208, faces 1244 and 1252 can contact each other and/or faces1248 and 1256 can contact each other (shown in FIG. 12B) to transferforces there between where gap G is eliminated.

FIG. 13A illustrates an isometric front view of anchor 1300 withextended tabs, in accordance with at least one example of thisdisclosure. FIG. 13B illustrates an isometric back view of anchor 1300with extended tabs, in accordance with at least one example of thisdisclosure. Anchor 1300 can include interlocking proximal supports,where medial and lateral tabs can interlock without connecting and canconnect to each other in response to forces to help limit relativemovement of extended tabs to help reduce accidental breakoff of theextensions from the anchor head. Many of the previously discussedanchors can be modified to include interlocking proximal supports.Anchor 1300 is discussed further below with respect to FIGS. 13A and13B. Note, the following discussion utilizes terms such as proximal,distal, medial, and lateral as relative directional references to assistthe reader with understanding the structure of the device. The devicedoes not necessarily have to be utilized with the various structuresaligned with a patient in accordance with these directions.

Anchor 1300 can include a head and extensions 1306 and 1308. Extension1306 can include elongate portion 1324 and proximal supports 1328 a and1328 b. Extension 1308 can include elongate portion 1326 and proximalsupports 1330 a and 1330 b. Extensions 1306 and 1308 can be separated,distal of proximal supports 1328 and 1330, by channels 1320, and canalso include groove 1362. Each of proximal supports 1328 a and 1328 bcan include proximal ramp 1371, proximal tongue 1372, proximal flat1373, medial ramp 1374, distal groove 1375, distal flat 1376, verticalface 1378, and distal ramp 1379. Each of proximal supports 1330 a and1330 b can include first proximal ramp 1381, proximal tongue 1382,second proximal ramp 1383, proximal groove 1384, proximal flat 1385,medial ramp 1386, distal tongue 1387, distal flat 1388, vertical face1389, and distal ramp 1390. Also shown in FIGS. 13A and 13B are axis A,forces F1, F2, F3, and F4, distance G, and orientation indicatorsProximal, Distal, Medial, and Lateral.

Groove 1362 can be a circumferential groove extending aroundsubstantially all of an outer portion of extensions 1306 and 1308, butcan be separated by proximal supports 1328 and 1330. In some examples,groove 1362 can be sized and shaped to receive a projection therein,such as one or more balls. The projection can engage the groove toretain extensions 1306 and 1308, such as within a sleeve orreinforcement tool.

Each of proximal supports 1328 a and 1330 a can terminate at opposingfaces defined by the various projections and grooves, discussed indetail further below. Each of the faces of portions of proximal supports1328 a and 1330 a can be parallel and separated by gap 1360 havingdistance G in a first condition (shown in FIG. 13B). Proximal supports1328 b and 1330 b can be similarly configured. Proximal supports 1328 aand 1328 b can include a geometry configured to engage proximal supports1330 a and 1330 b, respectively, in response to forces (such as F1, F2,and F3) to help limit unwanted or accidental separation of extensions1306 and 1308 from a head (such as head 102) of anchor 1300. Each of theproximal supports 1328 and 1330 extend radially inward from proximalsections of extensions 1306 and 1308 to engage opposing proximalsupports along gap 1360.

The portions of proximal support 1328 a can be connected as follows,proximal ramp 1371 can extend distally and laterally from a proximaltermination of proximal support 1328 a where proximal ramp 1371 cantransition into proximal tongue 1372. Proximal tongue 1372 can be alaterally extending protrusion or extension from proximal ramp 1371including a rounded termination, tongue, or nose that connects ortransitions to proximal flat 1373. Proximal flat 1373 can be asubstantially horizontal (with respect to an orientation of FIGS. 13Aand 13B) portion or segment of proximal support 1328 a extendingmedially from proximal tongue 1372 and connecting to medial ramp 1374.Medial ramp 1374 can extend medially and distally from proximal flat1373. In one example, medial ramp 1374 can be substantially orthogonal,though not directly connected, to proximal ramp 1371. Medial ramp 1374can connect to distal groove 1375 which can be a groove or recessextending medially and including a curved profile configured to connectmedial ramp 1374 to distal fiat 1376, which can be a substantiallyhorizontal portion extending laterally from distal groove 1375. Distalflat 1376 can be connected by a rounded corner to vertical face 1378,which can extend substantially distally from vertical face 1378 beforeconnecting to distal ramp 1379, which can extend distally and mediallyfrom vertical face 1378. The same portions of proximal support 1328 bcan be connected similarly. Further, each of proximal ramp 1371,proximal tongue 1372, proximal flat 1373, medial ramp 1374, distalgroove 1375, distal flat 1376, vertical face 1378, and distal ramp 1379can be connected by one or more transitions, such as corners or turnsthat can include a rounded or radiused profile.

The portions of proximal support 1330 a can be connected as follows,first proximal ramp 1381 can extend distally and medially from aproximal termination of proximal support 1330 a where first proximalramp 1381 can transition into proximal tongue 1382. Proximal tongue 1382can be a medially extending protrusion or extension from first proximalramp 1381 including a rounded termination, tongue, or nose that connectsor transitions to second proximal ramp 1383. Second proximal ramp 1383can extend laterally and distally from proximal tongue 1382substantially orthogonally to first proximal ramp 1381 (in someexamples) and can connect to proximal groove 1384. Proximal groove 1384can be a groove or recess extending laterally and including a curvedprofile configured to connect second proximal ramp 1383 to proximal flat1385. Proximal flat 1385 can be a substantially horizontal portion orsegment of proximal support 1330 a extending laterally from proximalgroove 1384 and connecting to medial ramp 1386. Medial ramp 1386 canextend substantially medially and distally from proximal flat 1385. Inone example, medial ramp 1386 can be substantially parallel to proximalramp 1381 and substantially orthogonal to second proximal ramp 1382.Distal tongue 1387 can connect to medial ramp 1386 and can extendsubstantially medially therefrom. Distal tongue 1387 can be a roundedtermination, tongue, or nose that connects or transitions to distal flat1388, which can extend substantially horizontally laterally from distaltongue 1387 and can connect to vertical face 1389. Distal flat 1388 beconnected by a rounded corner to vertical face 1389, which can extendsubstantially vertically distally from distal tongue 1388. Vertical face1389 can connect to distal ramp 1390, which can extend laterally anddistally therefrom and can be substantially parallel to second proximalramp 1383. The same portions of proximal support 1330 b can be connectedsimilarly. Further, each of first proximal ramp 1381, proximal tongue1382, second proximal ramp 1383, proximal groove 1384, proximal flat1385, medial ramp 1386, distal tongue 1387, distal flat 1388, verticalface 1389, and distal ramp 1390 can be connected by one or moretransitions, such as corners or turns that can include a rounded edgeand/or radiused profile.

The engagement and interaction between proximal supports 1328 a and 1330a are described with reference to operation of some examples below.Proximal ramp 1371 and proximal ramp 1381 can converge together as theyextend distally to substantially form a V-shape from a front view withrespect to FIGS. 13A and 13B. This configuration can allow proximal ramp1371 and proximal ramp 1381 to operate as lead-ins for a connectionmember or rod and/or an insertion tool. That is, a connection member,which can have a cylindrical cross-section, can be oriented with an axisof the connection member substantially orthogonally to axis A and can beinserted through proximal supports 1328 a and 1330 a (and proximalsupports 1328 b and 1330 b) by being forced (in a directionsubstantially parallel to axis A) into proximal ramp 1371 and proximalramp 1381. This engagement of the connection member with proximal ramp1371 and proximal ramp 1381 can force extension 1306 to move mediallyand extension 1308 to move laterally as proximal supports 1328 a and1330 a separate to allow the connection member to be woven proximally todistally through proximal supports 1328 a and 1330 a, with proximalsupports 1328 a and 1330 a (and proximal supports 1328 b and 1330 b)acting as guides. Further, second proximal ramp 1383 and medial ramps1374 and 1386 can further guide the connection member distally as it ispassed between proximal supports 1328 a and 1330 a and into channel 1320for further insertion into a head of anchor 1300.

As noted above, each transition between portion of proximal supports1328 a and 1330 a can be rounded and/or smooth, which can help reducecatching of the connection member on the various portions of proximalsupports 1328 a and 1330 a (and the portions therebetween) while theconnection member is being moved between proximal supports 1328 a and1330 a (and proximal supports 1328 b and 1330 b) to channel 1320. Forexample, proximal tongues 1371 and 1382 and distal tongue 1387 can berounded to help reduce friction (and catching) of the connection memberas it passes between the tongues and grooves.

The components of proximal supports 1328 a and 1330 a can provideadditional functionality. For example, during manipulation of anchor1300 (for example, during a spinal de-rotation procedure), variousforces can be applied to anchor 1300. In some examples, a tensile forcecan be applied to one extension, such as force F1 applied to extension1306 (as shown in FIG. 13B). Because the tensile force may beasymmetrically applied to extensions 1306 and 1308 (that is a tensileforce applied to extension 1306 may be greater than that applied toextension 1308), force F1 can cause movement, such as axial translation,of extension 1306 relative to extension 1308.

In some cases, this translation can cause premature or undesiredseparation of extension 1306 from a head of anchor 1300. However, here,contact between proximal supports 1328 a and 1330 a and between proximalsupports 1328 b and 1330 b can distribute the force to help limit breakoff. More specifically, when extension 1306 translates in a proximaldirection (direction of force F1), distal flat 1376 of proximal supports1328 a and 1328 b can contact distal flat 1388 of proximal supports 1330a and 1330 b, respectively, to transfer a portion of force F1 (in someexamples approximately half of the force) to extension 1308. Further,engagement between other complimentary portions of proximal supports1328 a and 1328 b and proximal supports 1330 a and 1330 b can furtherhelp to transfer force between extensions 1306 and 1308. For example,force transfer can occur between proximal ramp 1371 and second proximalramp 1383. These load transfers can help to prevent breakoff ofextension 1306 due to force F1 or other tensile forces.

Similarly, a force in the direction of F1 (of a proximal direction)applied to extension 1308 can be transferred to extension 1306 bycontact between proximal flat 1373 and proximal flat 1385. Further,engagement between other complimentary portions of proximal supports1328 a and 1328 b and proximal supports 1330 a and 1330 b can furtherhelp to transfer force between extensions 1306 and 1308. For example,force transfer can occur between medial ramp 1374 and medial ramp 1386.These load transfers can help to prevent breakoff of extension 1308 dueto a force similar to force F1 applied to extension 1308. Also, force F2applied to extension 1306 can cause a similar interaction.

In some examples, a force substantially or partially orthogonal to axisA can be applied to one or more extensions 1306 and 1308. For example,force F2 can be applied to extension 1306. In this example, thecomplimentary surfaces of proximal supports 1328 a and 1328 b andproximal supports 1330 a and 1330 b can contact each other to help limitpinching in. Specifically, vertical face 1378 and vertical face 1389 cancontact each other to transfer loads therebetween to limit pinching inand to limit bending of one extension (such as extension 1306) relativeto the other (such as extension 1308). Similarly, force F4 can betransferred between extensions 1306 and 1308 through complimentarysurfaces of proximal supports 1328 a and 1328 b and proximal supports1330 a and 1330 b, specifically vertical face 1378 and vertical face1389.

In some examples, such as during a de-rotation procedure, more than oneforce may be applied to extensions 1306 and 1308 using, for example, atool or one or more hands. During a de-rotation procedure, extensions1306 and 1308 can be grasped and a force can be applied to extension1306. For example, force F2 can be applied. Because a head of anchor1300 can be secured to a vertebra, force F2 can create a bending momenton extension 1306. Further, during de-rotation, a force, such as forceF4 can be applied to extension 1308 (at a position relatively lower thanforce F2), which can increase the moment about extensions 1306 and 1308.When a moment is created, asymmetric axial movement between extensions1306 and 1308 can occur. In this example, the moment can create aresultant force that causes proximal translation of extension 1306relative to extension 1308. However, as discussed above, because distalflat 1376 can contact distal flat 1388, relative proximal movement ofextension 1306 to extension 1308 can be limited, which can help preventundesired break-off of extension 1306 from the head by transferring loadto extension 1308. This design can also help allow a greater moment tobe applied to extensions 1306 and 1308 during a de-rotation procedure.

Distal ramp 1379 and distal ramp 1390 can converge together as theyextend distally to substantially form an upside down V-shape from afront view with respect to FIGS. 13A and 13B. Though the ramps arediscussed as having a V-shape, other shapes such as a U-shape can beused in other examples. This configuration can allow distal ramp 1379and distal ramp 1390 to function as lead-ins (or lead-outs) for aconnection member or rod and/or an insertion tool. That is, a connectionmember, which can have a cylindrical cross-section, can be removedthrough proximal supports 1328 a and 1330 a by being forced into distalramp 1379 and distal ramp 1390.

For example, when it is desired to remove a connection member fromchannels 1320 (for example, to reposition the connection member), theconnection member can be moved proximally within channels 1320 until theconnection member engages distal ramp 1379 and distal ramp 1390. Thisengagement can transform the proximally directed forces into medial andlateral forces to cause extensions 1306 and 1308 to separate so that theconnection member can be passed through proximal supports 1328 a and1328 b and 1330 a and 1330 b and removed from anchor 1300.

FIG. 14A illustrates a front view of anchor 1400 with extended tabs, inaccordance with at least one example of this disclosure. FIG. 14Billustrates an isometric front view of anchor 1400 with extended tabs,in accordance with at least one example of this disclosure. Anchor 1400can include interlocking proximal supports, where medial and lateraltabs can interlock without connecting and can contact each other inresponse to forces to limit relative movement of extended tabs to helplimit accidental breakoff. Anchor 1400 can also include asymmetricproximal supports such that a posterior support is a mirror of ananterior support to help reduce a size of the proximal supports. Any ofthe previously discussed anchors can be modified to include asymmetricinterlocking proximal supports. Anchor 1400 is discussed further belowwith respect to FIGS. 14A and 14B.

Anchor 1400 can include a head and extensions 1406 and 1408. Extension1406 can include elongate portion 1424 and proximal supports 1428 a and1428 b. Extension 1408 can include elongate portion 1426 and proximalsupports 1430 a and 1430 b. Extensions 1406 and 1408 can be separated,distal of proximal supports 1428 and 1430, by channels 1420, and canalso include groove 1462. Proximal support 1428 a can include proximalramp 1471 a, proximal tongue 1472 a, medial ramp 1474 a, distal groove1475 a, distal flat 1476, vertical face 1478 a, and distal ramp 1479.Proximal support 1428 b can include proximal ramp 1471 b, proximaltongue 1472 b, distal flat 1473 b, vertical face 1474 b, and distal ramp1475 b.

Proximal support 1430 a can include proximal ramp 1481 a, distal tongue1487 a, distal flat 1488 a, vertical face 1489 a, and distal ramp 1490a. Proximal support 1430 b can include proximal ramp 1481 b, proximaltongue 1482 b, medial ramp 1483 b, distal groove 1484 b, distal flat1485 b, vertical face 1486 b, and distal ramp 1487 b. Also shown inFIGS. 14A and 14B are axis A, forces F1, F2, F3, and F4, and orientationindicators Proximal, Distal, Medial, Lateral, Posterior and Anterior.

The portions of proximal supports 1428 a, 1428 b, 1430 a, and 1430 b canbe connected similarly to those of proximal supports 1328 a, 1328 b,1330 a, and 1330 b discussed above, except that, in this exampleproximal supports 1428 a and 1430 a can be asymmetric to proximalsupports 1428 b and 1430 b, which can help allow each of proximalsupports 1428 a, 1428 b, 1430 a, and 1430 b to be relatively smaller, asexplained further below.

Proximal supports 1428 a and 1430 a can interact to help resist relativemovement of extensions 1406 and 1408 in response to force F1 applied toextension 1406 while proximal supports 1428 b and 1430 b can interact tohelp resist relative movement of extensions 1406 and 1408 in response toforce F3 applied to extension 1406. For example, distal flat 1476 a anddistal flat 1488 a of proximal supports 1428 a and 1430 a can beconfigured to engage and transfer forces therebetween in response toforce F1 (or movement in a direction of force F1) to limit relativetranslation of extension 1406 to extension 1408, while distal flat 1473b and distal flat 1485 b of proximal supports 1428 b and 1430 b can beconfigured to engage and transfer forces therebetween in response toforce F3 (or movement in a direction of force F3) to limit relativetranslation of extension 1406 to extension 1408. In this way, proximalsupports 1428 a and 1430 a can transmit axial forces between extensions1406 and 1408 in one direction and proximal supports 1428 b and 1430 bcan transmit axial forces between extensions 1406 and 1408 in theopposite direction. That is, each set of proximal supports has only oneset of flats, but together the set of proximal supports limits axialtranslation in both directions. This can help allow each of proximalsupports 1428 a, 1428 b, 1430 a, and 1430 b to be relatively smaller(proximally to distally) in comparison to other supports that mayinclude multiple sets of flats on each set of supports, which can helpreduce cost.

In some examples, a force orthogonal to axis A can be applied to one ormore extensions 1406 and 1408. For example, force F2 can be applied toextension 1406. In this example, the complimentary surfaces of proximalsupports 1428 a and 1428 b and proximal supports 1430 a and 1430 b cancontact each other to help limit pinching in. Though many portions ofthe proximal supports can be configured to contact each other to helplimit pinching in, vertical faces 1478 a and 1489 a of proximal supports1428 a and 1430 a can be configured such that vertical faces 1478 b and1489 b of proximal supports 1428 b and 1430 b contact each other totransfer loads therebetween to limit pinching in and to limit bending ofone extension (such as extension 1406) relative to the other (such asextension 1408).

Proximal ramps 1471 and 1481 and distal ramps 1479 a, 1475 b, 1490 a,and 1487 b can be configured to allow a connecting member to separateproximal supports 1428 a and 1428 b from proximal supports 1430 a and1430 b during insertion and removal, respectively, of the connectingmember, as discussed above with respect to anchor 1300. However, becauseeach of proximal supports 1428 a and 1428 b and proximal supports 1430 aand 1430 b include fewer portions (because anterior proximal supports1428 a and 1430 a are asymmetric to posterior proximal supports 1428 band 1430 b) the connecting member can be more quickly and easily passedbetween proximal supports 1428 a and 1428 b from proximal supports 1430a and 1430 b.

FIG. 15A illustrates a front view of anchor 1500 with extended tabs, inaccordance with at least one example of this disclosure. FIG. 15Billustrates an isometric front view of anchor 1500 with extended tabs,in accordance with at least one example of this disclosure. Anchor 1500can include proximal supports that can lock (or fit together in aninterlocking manner) to limit unwanted separation of extended tabs,while still being separable to allow removal or break-off of theextended tabs from a head of anchor 1500. Any of the previouslydiscussed anchors can be modified to include locking proximal supports.Anchor 1500 is discussed further below with respect to FIGS. 15A and15B.

Anchor 1500 can include a head and extensions 1506 and 1508. Extension1506 can include elongate portion 1524 and proximal supports 1528 a and1528 b. Extension 1508 can include elongate portion 1526 and proximalsupports 1530 a and 1530 b. Extensions 1506 and 1508 can be separated,distal of proximal supports 1528 and 1530, by channels 1520. Each ofproximal supports 1528 a and 1528 b can include proximal ramp 1571,proximal vertical portion 1572 a, proximal recess 1573, finger 1574,distal recess 1574, distal vertical portion 1575, distal verticalportion 1576, and distal ramp 1577. Each of proximal supports 15′30 aand 1530 b can include proximal ramp 1581, proximal vertical portion1582, proximal extension 1583, finger recess 1584, distal extension1585, distal vertical portion 1586, and distal ramp 1587. Also shown inFIGS. 15A and 15B are forces F1, F2, F3, and F4, heights h1 and h2, andorientation indicators Proximal, Distal, Medial, Lateral, Anterior, andPosterior.

The components of proximal supports 1528 and 1530 can be connected suchthat proximal support 1528 locks with proximal support 1530 to helplimit separation of extensions 1506 and 1508 and to help limit pinchingin of extensions 1506 and 1508. More specifically, finger 1574 can be aprojection extending laterally from between proximal recess 1573 anddistal recess 1574, where finger 1574 has a maximum height h1 that islarger than height h2 between proximal recess 1573 and distal recess1574.

Proximal recess 1573 and distal recess 1574 can be sized and shapedcomplimentary to proximal extension 1583 and distal extension 1585,respectively, such that proximal extension 1583 and distal extension1585 can nest within proximal recess 1573 and distal recess 1574,respectively. Finger recess 1584 can be a recess extending into proximalsupport 1530 from between proximal extension 1583 and distal extension1585 and can be sized and shaped substantially complimentary to finger1574. In some examples, finger 1574 and recess 1584 can be substantiallyround or can have a substantially curved profile to allow a connectionmember to pass over and/or between finger 1574 and recess 1584.

Finger recess 1584 can be sized to receive finger 1574 therein. Whenfinger 1574 is disposed therein, lateral movement of finger 1584 can belimited by contact between a lateral portion of finger 1574 with alateral portion of finger recess 1584, such that finger 1574 is lockedor interlocked to finger recess 1584. In some examples, finger 1574 canbe disposed within finger recess 1584 similar to a puzzle pieceengagement. In this engagement, lateral movement of extension 1506 canalso be limited by contact between proximal vertical portion 1572 andproximal vertical portion 1582 and by contact between distal verticalportion 1576 and distal vertical portion 1586. Also, medial movement offinger 1574 can be limited by contact between a medial portion of finger1574 and proximal extension 1583 and by contact between finger 1574 anddistal extension 1585. This contact can help reduce medial movement offinger 1574 (and therefore proximal support 1528) relative to proximalsupport 1530 to help limit unwanted separation of extensions 1506 and1508 to help reduced unwanted break-off of extensions 1506 and/or 1508from the head of anchor 1500.

Further, engagement between a proximal portion of finger 1574 and recess1584 can help limit proximal movement of extension 1506 relative toextension 1508 (such as caused by force F1) and contact between a distalportion of finger 1574 and recess 1584 can help limit distal movement ofextension 1506 relative to extension 1508 (such as caused by force F3).

In operation of some examples, when separation of extension 1506 fromextension 1508 from each other is desired, for example, to remove eitherof extension 1506 and 1508 from the head, either of extension 1506 andextension 1508 can be moved posteriorly or anteriorly (with respect toFIG. 15) relative to the other of extension 1506 and extension 1508 todisengage finger 1574 from finger recess 1584. For example, extension1506 can be moved posteriorly relative to extension 1508 to move fingers1574 a and 1574 b out of finger recesses 1584 a and 1584 b(respectively) so that extensions 1506 and/or 1508 can be moved mediallyand/or laterally relative to each other. This can allow one or more ofextension 1506 and extension 1508 to be separated from a head orotherwise positioned as desired during a procedure.

FIG. 16 illustrates an isometric front view of anchor 1600 with extendedtabs, in accordance with at least one example of this disclosure. Anchor1600 can include extensions 1606 and 1608. Extension 1606 can includeproximal support 1628 and extension 1608 can include proximal support1630. Extensions 1606 and 1608 can be separated, distal of proximalsupports 1628 and 1630, by channels 1620. Proximal support 1628 caninclude finger 1670 including chamfers 1672, 1674, and 1676. Proximalsupport 1630 can include recess 1680. Also shown in FIG. 16 are axis Aand orientation indicators Proximal, Distal, Medial, and Lateral.

Anchor 1600 can be similar to those discussed above, except, thatproximal supports 1628 and 1630 can include finger 1670 includingchamfers 1672, 1674, and 1676 where recess 1680 can be sized and shapedcomplimentary to finger 1670 to receive finger 1670 therein. Chamfers1672, 1674, and 1676 (along with vertical and horizontal portions ofproximal supports 1628 and 1630) can help reduce pinching in ofextensions 1628 and 1630 and can help limit relative translation ofextensions 1628 and 1630, while chamfers 1672, 1674, and 1676 can helpallow a connection member to be passed through proximal supports 1628and 1630 without catching. In some examples, chamfers 1672, 1674, and1676 may be less expensive to manufacture than other shapes while stillhelping to reduce friction and catching of a connection member as itpasses between proximal supports 1628 and 1630.

FIG. 17 illustrates an isometric front view of anchor 1700 with extendedtabs, in accordance with at least one example of this disclosure. FIG.17 illustrates an isometric front view of anchor 1700 with extendedtabs, in accordance with at least one example of this disclosure. Anchor1700 can include extensions 1706 and 1708. Extension 1706 can includeproximal support 1728 and extension 1708 can include proximal support1730. Extensions 1706 and 1708 can be separated, distal of proximalsupports 1728 and 1730, by channels 1720. Proximal support 1728 caninclude recess 1770. Proximal support 1730 can include flat portions1782, 1784, and 1786. Also shown in FIG. 17 are axis A and orientationindicators Proximal, Distal, Medial, and Lateral.

Anchor 1700 can be similar to those discussed above, except thatproximal support 1730 can include finger 1780 which can be asubstantially rectangular projection extending medially from proximalsupport 1730. Flat portions 1782, 1784, and 1786 can engage recess 1770of proximal support 1728 can help reduce pinching in of extensions 1728and 1730 and can help limit relative translation of extensions 1728 and1730.

FIG. 18 illustrates a front view of anchor 1800 with extended tabs, inaccordance with at least one example of this disclosure. Anchor 1800 caninclude interlocking proximal supports having a constantly curvinggeometry (including no flat portions) to help reduce friction of aconnection member passing between the proximal supports. Any of thepreviously discussed anchors can be modified to include constantlycurving geometry.

Anchor 1800 can include extensions 1806 and 1808. Extension 1806 caninclude proximal support 1828 and extension 1808 can include proximalsupport 1830. Extensions 1806 and 1808 can be separated, distal ofproximal supports 1828 and 1830, by channels 1820. Proximal support 1828can include proximal finger 1870, medial finger 1872, and distal finger1874. Proximal support 1830 can include proximal finger 1880, medialfinger 1882, and distal finger 1884. Also shown in FIG. 18 are axis Aand orientation indicators Proximal, Distal, Medial, and Lateral.

Proximal finger 1870, medial finger 1872, and distal finger 1874 ofproximal support 1828 can interlock with proximal finger 1880, medialfinger 1882, and distal finger 1884 of proximal support 1830 to helplimit relative movement of extensions 1806 and 1808. Interlocking of thefingers of proximal support 1828 and proximal support 1830 can besimilar to a finger joint arrangement, except that each portion of thefingers of proximal support 1828 and proximal support 1830 can have acontinuously curving profile. That is, an outer portion of each ofproximal finger 1870, medial finger 1872, and distal finger 1874 ofproximal support 1828 and proximal finger 1880, medial finger 1882, anddistal finger 1884 of proximal support 1830 can be without a flatportion, such that, together, the fingers form an interface having asnaking profile. This geometry and arrangement can help reduce frictionor catching on a connection member when the connection member is passedbetween proximal supports 1828 and 1830. However, because each ofproximal supports 1828 and 1830 includes three interlocking fingers,there can be a large contact area between proximal supports 1828 and1830, which can help improve force transmission between proximal finger1870, medial finger 1872, and distal finger 1874 of proximal support1828 and proximal finger 1880, medial finger 1882, and distal finger1884 of proximal support 1830 to help limit relative translation ofextensions 1806 and 1808. Though three fingers of proximal supports 1828and 1830 can provide a large contact area, less fingers (such as one ortwo) or more fingers (such as four, five, or the like) can be used inother examples.

FIG. 19 illustrates a front view of anchor 1900 with extended tabs, inaccordance with at least one example of this disclosure. Anchor 1900 caninclude interlocking proximal supports having a curving geometry(including no axial flat portions or axially transverse flat portions)to help reduce friction of a connection member passing between theproximal supports. Any of the previously discussed anchors can bemodified to include curving geometry.

Anchor 1900 can include extensions 1906 and 1908. Extension 1906 caninclude proximal support 1928 and extension 1908 can include proximalsupport 1930. Extensions 1906 and 1908 can be separated, distal ofproximal supports 1928 and 1930, by channels 1920. Proximal support 1928can include proximal finger 1970 and distal finger 1972. Proximalsupport 1930 can include proximal finger 1980, medial finger 1982, anddistal finger 1984. Also shown in FIG. 19 are axis A and orientationindicators Proximal, Distal, Medial, and Lateral.

Proximal finger 1970 and distal finger 1972 of proximal support 1928 caninterlock with proximal finger 1980, medial finger 1982, and distalfinger 1984 of proximal support 1930 to help limit relative movement ofextensions 1906 and 1908. Interlocking of the fingers of proximalsupport 1928 and proximal support 1930 can be similar to a finger jointarrangement, except that each portion of the fingers of proximal support1928 and proximal support 1930 can have a curving profile terminationwith a straight portion connecting the curving terminations.

That is, a termination of each finger can be curved. For example, alateral-most portion of proximal finger 1970 can be curved and can beconnected to substantially straight portions on either side. However,the straight portions are not axially aligned (vertical with respect toFIG. 19) or axially tangential (horizontal with respect to FIG. 19).Further, each of proximal finger 1970 and distal finger 1972 can beseparated by a recess configured to receive finger 1982, where therecess is sized and shaped complementary to finger 1982. Thisarrangement of proximal finger 1970, distal finger 1972, proximal finger1980, medial finger 1982, and distal finger 1984 can form an interfacehaving a substantially snaking profile. This geometry and arrangementcan help reduce friction or catching on a connection member when theconnection member is passed between proximal supports 1928 and 1930.However, because proximal support 1928 includes two interlocking fingersand proximal support 1930 includes three interlocking fingers, there canbe a large contact area between proximal supports 1928 and 1930, whichcan help limit relative translation of extensions 1906 and 1908.

FIG. 20A illustrates a front view of anchor 2000 with extended tabs, inaccordance with at least one example of this disclosure. FIG. 20Billustrates an isometric view of anchor 2000 with extended tabs, inaccordance with at least one example of this disclosure. FIG. 20Cillustrates an isometric top view of anchor 2000 with extended tabs, inaccordance with at least one example of this disclosure. FIG. 20Dillustrates an isometric side view of anchor 2000 with extended tabs, inaccordance with at least one example of this disclosure. Anchor 2000 caninclude proximal supports having one or more chamfers extendingproximally to distally and anteriorly to posteriorly on proximal and/ordistal portions of the proximal supports to help guide insertion andremoval of a connection member between the extended tabs through theproximal supports where the connection member is being inserted from theanterior or posterior with respect to FIG. 20B. Any of the previouslydiscussed anchors can be modified to include chamfered proximalsupports. Anchor 2000 is discussed in further detail below with respectto FIGS. 20A-20C.

Anchor 2000 can include extensions 2006 and 2008. Extension 2006 caninclude proximal support 2028 and extension 2008 can include proximalsupport 2030. Extensions 2006 and 2008 can be separated, distal ofproximal supports 2028 and 2030, by channels 2020. Proximal support 2028can include finger 2070, recess 2072, finger 2074, proximal chamferportion 2076, and distal chamfer portion 2078. Proximal support 2030 caninclude finger 2080, recess 2082, finger 2084, proximal chamfer portion2086, and distal chamfer portion 2088. Also shown in FIG. 20 are axis A,thicknesses t1 and t2, and orientation indicators Proximal, Distal,Medial, Lateral, Anterior, and Posterior.

Anchor 2000 can be connected similarly to anchors discussed above wherefinger 2070 of proximal support 2028 can extend into recess 2082 ofproximal support 2030, and where recess 2082 can have a complimentaryshape and sized to finger 2070 such that proximal support 2028 and 2030interlock. Similarly, finger 2084 can extend medially from proximalsupport 2030 into recess 2072 of proximal support 2028. In theseconfigurations, proximal supports 2028 and 2030 can help limit pinchingin of extensions 2006 and extensions 2008 and can help limit axialrelative translation of extensions 2006 and 2008 to help limit unwantedbreakoff from a head of anchor 2000.

Proximal chamfer portion 2076 can be a chamfer in proximal finger 2072which can have thickness t1 at a proximal end that is smaller thanthickness t2, which can be a thickness of finger 2070 distal of theproximal portion (t2). That is, proximal chamfer 2076 portion can beginat a proximal beginning of finger 2070 and can extend distallytherefrom. Similarly, proximal chamfer portion 2076 can be a chamfer inproximal finger 2080 which can have thickness t1 at a proximal end thatis smaller than thickness t2, which can be a thickness of finger 2080distal of the proximal portion.

Distal chamfer portion 2078 and distal chamfer portion 2088 can be theopposite of proximal chamfer portions 2076 and 2086, where each ofdistal chamfer portion 2078 and distal chamfer portion 2088 begin at adistal portion of proximal supports 2028 and 2030, respectively, andincrease in thickness as they extend proximally. In some examples,proximal chamfer portions 2076 and 2086 can have a substantially U-shapefrom an anterior perspective (as shown in FIG. 20A) and distal chamferportions 2078 and 2088 can have a substantially upside-down shape froman anterior perspective (as shown in FIG. 20A). In other examples,proximal chamfer portions 2076 and 2086 can have other shapes, such asV, or the like. In some examples, proximal chamfer portions 2076 and2086 and distal chamfer portions 2078 and 2088 can form mirrors of thesame shape and in other examples, proximal chamfer portions 2076 and2086 and distal chamfer portions 2078 and 2088 can have different shapesand different sizes.

In operation of some examples, where it is desired to insert aconnection member into channels of anchor 2000 between extensions 2006and 2008 for reduction into a head of the anchor, it may be preferableor necessary to insert the connection member into anchor 2000 at anangle. Because the connection member must pass between proximal supports2028 and 2030, it may be difficult to insert the connection memberbetween proximal supports 2028 and 2030 in a direction not parallel toaxis A. The example of FIG. 20 addresses this issue by includingchamfers proximal chamfers 2076 and 2086 and distal chamfers 2078 and2088.

Because proximal chamfer portions 2076 and 2086 have a reduced thicknesst1 at a proximal portion, a connection member can be inserted in adirection not parallel to axis A. For example, the connection member canengage proximal chamfer portions 2076 and 2086 oriented at an angle of75 degrees from axis A (an axis of the connection member can beapproximately 75 degrees from axis A). Because proximal chamfer portions2076 and 2086 reduce in thickness towards the proximal side of proximalsupports 2028 and 2030, proximal chamfer portions 2076 and 2086 can be alead in for insertion in this direction, where proximal chamfer portions2076 and 2086 direct the connection members radially inward andpartially distally as the connection member separates proximal supports2028 and 2030 to enter channels 2030. Similarly, distal chamfer portions2078 and 2088 can help guide removal of the connection member fromchannels 1230 from a direction not parallel to axis A (an axis of theconnection member is at an angle not perpendicular to axis A). Thoughinsertion of the connection member is discussed at an angle of 75degrees, insertion at other angles is possible and proximal supports2028 and 2030 can be configured to accept insertion at angles greaterthan 75 degrees.

FIG. 21 illustrates a front view of anchor 2100 with extended tabs, inaccordance with at least one example of this disclosure. Anchor 2100 caninclude extensions 2106 and 2108. Extensions 2106 and 2108 can beseparated, distal of proximal supports 2128 and 2130, by channels 2120.Extension 2106 can include proximal supports 2128 and extension 2108 caninclude proximal supports 2130. Proximal support 2128 can include finger2170 and recess 2172. Proximal support 2130 can include recess 2180 andfinger 2182.

Anchor 2100 can be similar to anchor 1300 discussed above, except thatthe curves of anchor 2100 (finger 2170 and 2182 and recesses 2180 and2172, for example) can have relatively larger radii of curvature. Thiscan help reduce catching of a connection member that is being insertedinto or removed from channels 2120 as the connection member passesbetween proximal supports 2128 and 2130.

NOTES AND EXAMPLES

The following, non-limiting examples, detail certain aspects of thepresent subject matter to solve the challenges and provide the benefitsdiscussed herein, among others.

Example 1 is an anchor coupleable to a bone, the anchor comprising: ahead including distal head portion and a proximal head portion, theproximal head portion open at a proximal end of the head; a shankextending distally from the distal head portion, the shank including athreaded portion configured to engage the bone; a first extensioncomprising: a first breakaway portion coupling the first extension tothe proximal head portion, the first extension separable from the headat the first breakaway portion; a first elongate portion extending froma first end proximate the first breakaway portion to a second end alonga longitudinal axis of the anchor, the first elongate portion includinga length sufficient to extend the second end outside an incision whenthe shank is engaged in the bone; and a first proximal support coupledto the second end of the first elongate portion, the proximal supportextending transverse to the longitudinal axis; and a second extensionopposing the first extension, the second extension comprising: a secondbreakaway portion coupling the second extension to the proximal headportion, the second extension separable from the head at the secondbreakaway portion; a second elongate portion extending from a first endproximate the first breakaway portion to a second end along alongitudinal axis of the anchor, the first elongate portion including alength sufficient to extend the second end outside an incision when theshank is engaged in the bone; and a second proximal support coupled tothe second end of the first elongate portion, the proximal supportextending transverse to the longitudinal axis, the first proximalsupport portion and the second proximal support portion separated in afirst condition and engaged to transfer forces there between in a secondcondition; and wherein the first and second extensions comprise athreaded portion on internal faces of the first and second extensions,the threaded portion extending distally from the first and secondextensions into the head portion.

In Example 2, the subject matter of Example 1 optionally includeswherein the head includes a first side and a second side each open tosubstantially form a u-shape adapted to receive a connecting rod.

In Example 3, the subject matter of any one or more of Examples 1-2optionally include wherein the first proximal support portion furthercomprises a first pair of arms extending transversely to thelongitudinal axis of the anchor toward the second proximal support, andwherein the second proximal support portion further comprises a secondpair of arms extending transversely to the longitudinal axis of theanchor toward the first proximal support.

In Example 4, the subject matter of Example 3 optionally includeswherein the first pair of arms comprises a first arm and a second armand the second pair of arms comprises a third arm and a fourth arm, thefirst arm and the third arm separated in the first condition and engagedto transfer forces there between in the second condition.

In Example 5, the subject matter of Example 4 optionally includeswherein the first arm and second arm together with the first elongateportion form a first substantially c-shape and wherein the third arm andthe fourth arm together with the second elongate portion form a secondsubstantially c-shape larger than the first substantially c-shape.

In Example 6, the subject matter of Example 5 optionally includeswherein the first substantially c-shape is nestable within the secondsubstantially c-shape.

In Example 7, the subject matter of any one or more of Examples 4-6optionally include wherein the first arm terminates at a first end, thesecond arm terminates at a second end, the third arm terminates a thirdend proximate the first end, and the fourth arm terminates at a fourthend proximate the second end.

In Example 8, the subject matter of Example 7 optionally includeswherein the third arm comprises an undercut proximate the third end andthe fourth arm comprises an undercut proximate the fourth end, the firstend and second end nestable in the undercuts of the third end and fourthend, respectively.

In Example 9, the subject matter of any one or more of Examples 7-8optionally include wherein the first end includes a first face, thesecond end includes a second face, the third end includes a third face,and the fourth end includes a fourth face, the first and third facesseparated by a gap in the first condition and engageable in the secondcondition, and the second and fourth faces separated by a second gap inthe first condition and engageable in the second condition.

In Example 10, the subject matter of Example 9 optionally includeswherein first face and second face are coplanar along a first plane andthe third face and fourth face are coplanar along a second plane, thefirst and second planes substantially parallel with each other and witha diameter through the longitudinal axis.

In Example 11, the subject matter of Example 10 optionally includeswherein the first face and the third face are substantially parallelwith each other in the first condition and the second face and thefourth face are substantially parallel with each other in the firstcondition.

In Example 12, the subject matter of Example 11 optionally includeswherein the first face and third face are parallel to a first plane andthe second face and the fourth face are parallel to a second plane, thefirst and second planes substantially parallel with different chordstransverse to the longitudinal axis.

In Example 13, the subject matter of any one or more of Examples 7-12optionally include wherein the first and second ends include anincreased cross-section to the third and fourth ends.

Example 14 is an anchor coupleable to a bone, the anchor comprising: ahead including distal head portion and a proximal head portion, theproximal head portion open at a proximal end of the head; a shankextending distally from the distal head portion, the shank including athreaded portion configured to engage the bone; a first extensionextending from a first Breakaway portion coupling the first extension tothe proximal head portion, the first extension forming a firstsemi-cylindrical wall sharing a longitudinal axis with the head andincluding a length extendable beyond an incision when the shank isengaged in the bone, the first extension comprising: a first supportcoupled to a proximal end of the first semi-cylindrical wall, the firstsupport extending transverse to the longitudinal axis; and a secondextension extending from a second Breakaway portion coupling the second.extension to the proximal head portion, the second extension forming asecond semi-cylindrical wall sharing the longitudinal axis with the headand including a length extendable beyond an incision when the shank isengaged in the bone, the second extension comprising: a second supportcoupled to a proximal end of the second semi-cylindrical wall, thesecond support extending transverse to the longitudinal axis, the firstsupport and the second proximal support separate and engageable totransfer forces there between.

In Example 15, the subject matter of Example 14 optionally includeswherein the first breakaway portion includes a thickness that is smallerthan a thickness of the first semi-cylindrical wall.

In Example 16, the subject matter of any one or more of Examples 14-15optionally include wherein the first semi-cylindrical wall and thesecond semi-cylindrical wall together substantially have a geometricshape of a hollow cylinder about the longitudinal axis, the firstsemi-cylindrical wall and the second semi-cylindrical wall separated bya pair of longitudinally extending slots configured to receive aconnecting member therethrough.

In Example 17, the subject matter of any one or more of Examples 14-16optionally include wherein the first support comprises a first armterminating at a first end and a second arm terminating at a second end,and wherein the second support comprises a third arm terminating at athird end and a fourth arm terminating at a fourth end.

In Example 18, the subject matter of Example 17 optionally includeswherein the first end includes a first notch configured to receive thethird end and the second end includes a second notch configured toreceive the fourth end, wherein the notch and second notch each includean outer sidewall extension radially overlapping respective portions ofthe third and fourth arms.

Example 19 is an implant system for securing an anchor to a bone, thesystem comprising: an anchor comprising: a head open at a proximal endof the head; a shank extending distally from the head, the shankincluding a threaded portion configured to engage the bone; a firstextension extending from a first Breakaway portion coupling the firstextension to the proximal head portion, the first extension forming afirst semi-cylindrical wall sharing a longitudinal axis with the headand including a first support coupled to a proximal end of the firstsemi-cylindrical wall, the first support extending transverse to thelongitudinal axis, the first extension including a recess on an outersurface; a second extension extending from a second Breakaway portioncoupling the second extension to the proximal head portion, the secondextension forming a second semi-cylindrical wall sharing thelongitudinal axis with the head and including a second support coupledto a proximal end of the second semi-cylindrical wall, the secondsupport extending transverse to the longitudinal axis toward the firstsupport, the first and second extensions separated by first and secondextension slots configured to receive a connecting member therethrough;a sleeve adapted to reinforce the anchor, the sleeve comprising: a firstsleeve arm and a second sleeve arm together extending longitudinally toform a longitudinal bore open at a distal end of the sleeve to receivethe first extension and the second extension therein, the first andsecond sleeve arms separated by first and second sleeve slots alignablewith the first and second extension slots to receive the connectingmember therethrough; and an actuator disposed on an outer surface of oneof the first and second sleeve arms, the actuator engageable with therecess of the first extension to restrict movement of the anchorrelative to the sleeve, the actuator actuatable to release the sleevefrom the anchor.

In Example 20, the subject matter of Example 19 optionally includeswherein the sleeve is sized to limit relative movement of the first andsecond extensions.

In Example 21, the subject matter of any one or more of Examples 19-20optionally include a proximal portion coupling the first sleeve arm andthe second sleeve arm proximate a proximal termination of the firstsleeve arm and the second sleeve arm.

In Example 22, the subject matter of any one or more of Examples 19-21optionally include the proximal portion further comprising: a projectionextending radially inward from the proximal portion to engage a proximalend of one of the first semi-cylindrical wall and secondsemi-cylindrical wall, the projecting limiting axial translation of theanchor relative to the sleeve.

In Example 23, the apparatuses or method of any one or any combinationof Examples 1-22 can optionally be configured such that all elements oroptions recited are available to use or select from.

The above detailed description includes references to the accompanyingdrawings, which form a part of the detailed description. The drawingsshow, by way of illustration, specific embodiments in which theinvention can be practiced. These embodiments are also referred toherein as “examples.” Such examples can include elements in addition tothose shown or described. However, the present inventors alsocontemplate examples in which only those elements shown or described areprovided. Moreover, the present inventors also contemplate examplesusing any combination or permutation of those elements shown ordescribed (or one or more aspects thereof), either with respect to aparticular example (or one or more aspects thereof), or with respect toother examples (or one or more aspects thereof) shown or describedherein.

In the event of inconsistent usages between this document and anydocuments so incorporated by reference, the usage in this documentcontrols.

In this document, the terms “a” or “an” are used, as is common in patentdocuments, to include one or more than one, independent of any otherinstances or usages of “at least one” or “one or more.” In thisdocument, the term “or” is used to refer to a nonexclusive or, such that“A or B” includes “A but not B,” “B but not A,” and “A and B,” unlessotherwise indicated. In this document, the terms “including” and “inwhich” are used as the plain-English equivalents of the respective terms“comprising” and “wherein.” Also, in the following claims, the terms“including” and “comprising” are open-ended, that is, a system, device,article, composition, formulation, or process that includes elements inaddition to those listed after such a term in a claim are still deemedto fall within the scope of that claim. Moreover, in the followingclaims, the terms “first,” “second,” and “third,” etc. are used merelyas labels, and are not intended to impose numerical requirements ontheir objects.

The above description is intended to be illustrative, and notrestrictive. For example, the above-described examples (or one or moreaspects thereof) may be used in combination with each other. Otherembodiments can be used, such as by one of ordinary skill in the artupon reviewing the above description. The Abstract is provided to complywith 37 C.F.R. § 1.72(b), to allow the reader to quickly ascertain thenature of the technical disclosure. It is submitted with theunderstanding that it will not be used to interpret or limit the scopeor meaning of the claims. Also, in the above Detailed Description,various features may be grouped together to streamline the disclosure.This should not be interpreted as intending that an unclaimed disclosedfeature is essential to any claim. Rather, inventive subject matter maylie in less than all features of a particular disclosed embodiment.Thus, the following claims are hereby incorporated into the DetailedDescription as examples or embodiments, with each claim standing on itsown as a separate embodiment, and it is contemplated that suchembodiments can be combined with each other in various combinations orpermutations. The scope of the invention should be determined withreference to the appended claims, along with the full scope ofequivalents to which such claims are entitled.

1. An implant system for securing an anchor to a bone, the system comprising: an anchor comprising: a head including a proximal end with an opening configured to receive an elongate member running transverse to a longitudinal axis of the anchor; a shank extending distally from the head, the shank including a threaded portion configured to engage the bone; a first extension extending from a first breakaway portion coupling the first extension to the head, the first extension forming a first semi-cylindrical wall sharing the longitudinal axis with the head; a second extension extending from a second breakaway portion coupling the second extension to the head, the second extension forming a second semi-cylindrical wall sharing the longitudinal axis with the head; and a sleeve adapted to reinforce the anchor, the sleeve comprising: a first sleeve arm and a second sleeve arm together extending longitudinally to form a longitudinal bore open at a distal end of the sleeve to receive the first extension and the second extension therein; and an actuator engageable with the first extension to restrict movement of the anchor relative to the sleeve, the actuator operable to release the sleeve from the anchor.
 2. The system of claim 1, wherein the first extension includes a recess on an outer surface of the first extension, wherein the actuator includes a projection insertable into the recess to lock the sleeve to the anchor, and wherein the actuator is operable to retract the projection from the recess to unlock the sleeve from the anchor.
 3. The system of claim 2, wherein the actuator is movable between a locked position where the projection is positioned in the recess and an unlocked position where the projection is retracted from the recess, and wherein the actuator is biased toward the locked position.
 4. The system of claim 3, wherein the actuator is located at an outer surface of the first sleeve arm.
 5. The system of claim 4, wherein the actuator is located on a proximal portion of the first sleeve arm.
 6. The system of claim 5, wherein the actuator is recessed into the proximal portion of the first sleeve arm.
 7. The system of claim 6, wherein a button portion of the actuator extends beyond a radial outer surface of the first sleeve arm when the actuator is in the locked position.
 8. The system of claim 1, wherein the first and second extensions are separated by first and second extension slots configured to receive a connecting member therethrough, and wherein the first and second sleeve arms separated by first and second sleeve slots aligned with the first and second extension slots when the first and second extensions are inserted into the sleeve, the first and second sleeve slots configured to receive the connecting member therethrough.
 9. The system of claim 1, wherein the first extension includes a first support coupled to a proximal end of the first semi-cylindrical wall, the first support extending transverse to the longitudinal axis, and wherein the second extension includes a second support coupled to a proximal end of the second semi-cylindrical wall, the second support extending transverse to the longitudinal axis toward the first support.
 10. The system of claim 1, further comprising: a proximal portion coupling the first sleeve arm and the second sleeve arm proximate a proximal termination of the first sleeve arm and the second sleeve arm, the proximal portion including a projection extending radially inward from the proximal portion to engage a proximal end of one of the first semi-cylindrical wall and second semi-cylindrical wall to limit axial translation of the anchor relative to the sleeve.
 11. An implant system for securing an anchor to a bone, the system comprising: an anchor comprising: a U-shaped head open at a proximal end thereof; a shank extending distally from the head and including a threaded portion configured to engage the bone; a first extension connected to a first side of the U-shaped head by a first breakaway portion and extending therefrom; a second extension connected a second side of the U-shaped the head by a second breakaway and extending therefrom; and a sleeve adapted to reinforce the anchor, the sleeve comprising: a first sleeve arm and a second sleeve arm together forming a longitudinal bore open at a distal end of the sleeve to receive the first extension and the second extension therein; and an actuator engageable with the first extension to restrict movement of the anchor relative to the sleeve, the actuator operable to release the sleeve from the anchor.
 12. The system of claim 11, wherein the first extension includes a recess on an outer surface of the first extension, the actuator positionable within the recess to lock the sleeve to the anchor, wherein the actuator includes a projection extending therefrom insertable into the recess, and wherein the actuator is operable to retract the projection from the recess to unlock the sleeve from the anchor.
 13. The system of claim 12, wherein the actuator is movable between a locked position where the projection is positioned in the recess and an unlocked position where the projection is retracted from the recess, and wherein the actuator is biased toward the locked position.
 14. The system of claim 13, wherein the actuator is located on an outer surface of a proximal portion of the first sleeve arm.
 15. The system of claim 14, wherein the actuator is recessed into the proximal portion of the first sleeve arm.
 16. The system of claim 15, wherein a button portion of the actuator extends beyond a radial outer surface of the first sleeve arm when the actuator is in the locked position.
 17. The system of claim 11, wherein the first and second extensions are separated by first and second extension slots configured to receive a connecting member therethrough, and wherein the first and second sleeve arms separated by first and second sleeve slots alignable with the first and second extension slots to receive the connecting member therethrough.
 18. The system of claim 11, further comprising: a proximal portion coupling the first sleeve arm and the second sleeve arm proximate a proximal termination of the first sleeve arm and the second sleeve arm, the proximal portion including a plurality of projections each extending radially inward to engage the first extension and the second extension to limit axial translation of the anchor relative to the sleeve.
 19. The system of claim 18, wherein the first extension and the second extension define a plurality of notches at a proximal portion of the first extension and the second extension, each of the plurality of notches configured to receive one projection of the plurality of projections therein when the first extension and the second extension are inserted into the first sleeve arm and the second sleeve arm, respectively, to limit rotation of the anchor with respect to the sleeve.
 20. The system of claim 19, wherein the plurality of projections each have a triangular shape from a proximal perspective. 